Drill bits used to drill wellbores have to operate in an extremely hostile environment. As a result, such drill bits are highly specialized for their purpose. One such drill bit is of the type known as a roller cone bit, in which cutting elements are mounted on cones which rotate as the drill bit is rotated downhole to drill a wellbore.
To facilitate rotation of the cones, bearings are provided between the cones and a body of the bit, and lubricant is provided for the bearings. To prevent external debris from damaging the bearings or otherwise causing excessive wear in the rotating cones, and to prevent escape of the lubricant, seals are also provided in such bits.
Unfortunately, in the harsh downhole environment, seals in drill bits tend to fail (e.g., permit excessive wear, no longer exclude debris, fail to contain the lubricant, etc.) sooner than is desired. Drilling operations could be made much more economical and expeditious if drill bit seals had longer lives.